Apparatus for dry generation of acetylene



ATTORNEY Aug-23, 1932. R. s. JANE APPARATUS FOR DRY GENERATION OFACETYLENE Filed Oct. 23, 1931' Fllll o ran STA Patented a 23, 1932 TrisROBERT S. JANE, OF SHAWINIGAN FALLS, QUEBEC, CANADA, ASSIGNOR T0SEAWINIGAN CHEMICALS LIMITED, 0] MONTREAL, QUEBEC, CANADA APPARATUS ronnay GENERATION or Acnmm Application filed October 23, 193i,Ser1alRo.570, 879, and in Canada m 16, iaeol.

Application for Letters Patent of the Dominion of Canada, Serial Number364,804, has been filed the 16th May, 1930.

This invention relates to improvements 1n apparatus for hydratin calciumcarbide, and the principal objects 0% the invention are to enablethe'""production of substantiall dry acetylene gas and the completehydratlon of the carbide. Various other objects and the advantages ofthe invention may be ascertained from the following description.

In the ordinary processes of hydrating calcium carbide for production ofacetylene gas, by feeding carbide into water, an appreciable percentageof the carbide escapes hydration, 1n spite of the use of a great excessofwwater, owing to the adherence of hydrate to the lumps of carbide. Thegas produced is substantially saturated with water vapour, necessitatingdryin K In greater feeding the carbide into a rotating screen containedin a rotating drum and sprayin the carbide within the screen with acalculate amount of water. The tumbling action of the screenIGIIIOVGSfthG hydrate from the sur- 'face of the carbide lumps, thuskeeping the carbide exposed for hydration by the water.

Fine particles of carbide which pass the screen are tumbled in the drumand freed from adherent hydrate, so that theyarecompletely hydrated andserve to absorb, water from the hydrate, thus producing a substantiallydry pulverulent hydrate, absolutely free from carbide, which may beeasily handled and which is in excellent condition y for admixture withcarbon for the manufacture of further carbide. The water supplied isthat necessary for complete hydratlon of the-carbide and that necessaryto absorb, by evaporation, suflicient of the heat of reaction to renderthe process entirely safe. acetylene gas produced contains very muchless water than gas made by ordinary wet processes and, in consequence,since water always contains a certain amount of air in solution, lessair than gas produced by ordinary methods.

In the accompanying drawing which illustrates one embodiment of theinvention, but

stall, the invention resides in The Y to the details of which theinvention is not confined, since modifications and substitutions ofequivalents ma be efl'ected Fig. 1 is a vertical ongitudinal sectional Iview of an acetylene generator.

' Fig. 2 is a cross sectional view on the line 2-2 of Figure 1.

Referring more particularly to the drawing, 11 designates a closedhopper bottom carbide container mounted upon and discharging by gravityinto a primary feed take by any suitablemeans 17. The carbide isadvanced through the secondary conduit by a feed screw 18. Y Acylindrical hydrating drum 19 is rotatably mounted in bearings 20 bymeans of axially disposed hollow trunnions 21 and 22 at its oppositeends, the former of which, trunnions is in alignment with the conduit15"and is connected thereto by stufling box 23 secured to the conduit,The trunnion 22 passes through a stuifing box 24 into a closed hop'perbottom hydrate receiver 25, to which the stuffing box is secured; Acylindrical screen 26 of smaller diameter than the drum is arrangedcoaxially within the drum and extends from the feeding end of the drumfor a suitable distance toward the discharge end, usually somewhat morethan half the length of the drum. The inner end of the screen is closedby a centrally apertured plate 27 supported by a spider 28 connectedwith the inner surface of the drum. The screen is provided internallywith ribs 29 which serve to tumble carbide in the screen as it rotates.The mesh of the screen is of such size that it will not become cloggedwith example, the mesh may be between one-fifth and one-twentieth of aninch. The screen is preferabl of wire in order to have the maximum 0screening capacity. Theinnersurface of the drum between the feeding endand the spider 28 is provided with helical ribs 30 of suitable pitchwhich serve to work the hydrate toward the discharge end of the drum.Between the spider 28 and the discharge end of the drum, theinnersurface thereof is provided with ribs 31 disposed parallel orsubstantially parallel with the drum axis and adapted to tumble thehydrate andsmall carbide particles which have passed through the screenfor removal of hydrate from the surface of the carbide par- .ticles andexposure of the carbide to damp hydrate. The screen end plate carries afrusto-conical shield 32 overits central aperture to prevent hydrateentering into the screen through said aperture. At the dis charge end ofthe drum, a discharge cone 33 is mounted coaxial of the drumby means ofa spider 34, the apex of the cone projecting into the discharge trunnion22. The inner surface of the trunnion 22 is provided with helical ribs35 which cause the hydrate to move longitudinally through the trunnionand discharge into the receiver 25. valved water supply pipe 36 passesaxially through the discharge trunnion into the,

screen, being supported by the discharge cone and the spider 28.Within'the screen, the pipe extends upwardly and then longitudinally ofthe screen. This pipe is provided with apertures or nozzles 37 adaptedtodirect water in fine sprays or jets against the carbide only on theupwardly moving side of the screen at approximately the level where thecarbide reaches the limit of its angle of repose and falls from theribs29.

The hydrate receiver 25 discharges through a valve 38 into a furtherclosed hopper bottom receptacle 39, which discharges through a valve 40..A gas outlet pipe 41 leads from the top of the receiver 25 which may beprovided with a thermometer 42 and ,manometer 43.

The feed screws and drum are rotated by any suitable means, such as amotor 44 and suitable drive 45 between the motor and the feed screws anddrum. g

The operation of the device is as follows The valve 16 is closed toexclude air from the drum and the hopper 11 filled with car bide andclosed. The valve 16is then opened and the apparatus set in motion. Thescrew 13 feeds carbide past the open valve 16 so that it falls into theconduit and trunnion 21 into the rotating screen, wherein it is tumbledand sprayed with water. The water strikes the carbide at the upper limitof its movement so that water not absorbed by the most elevated carbidetrickles down over carbidekbelow. The gas escapes through the screeninto thedrum and flows through the trunnion 22 into the receiver 25. Themation of the screen and the action of the lifting ribs 29 causes thecarbide to be tumbled, so that the hydrate is separated and passesthrough the screen leaving the carbide exposed for further hydration.The amount of water is regulated to substantially that necessar forcomplete hydration of the carbide an that necessary to absorb, byevaporation, a substantial part of the heat of reaction. The hydratepassing through the screen contains suflicient water for hydration ofthe small particles-of carbide which also pass through the screen. Thedam hydrate and small particles of carbide are ed by the helical ribs 30toward the discharge end of the drum where they are tumbled until thesmall particles of carbide are completely hydrated and the'hydratesubstantially dried. by absorption of water therefrom in the hydrationof the small carbide particles. Under proper conditions the hydratepassing through the screen will contain about 15% of its weight ofmoisture and this moisture content will be reduced to about 3% to 5% inthe hydration of the small carbide particles. Hydrate containing thissmall amount of moisture is a A dry powder which is easily evacuatedfrom the drum by means of the discharge cone and .the helical ribs 35 inthe trunnion 22. When sufiicient hydrate. accumulates'in the receiver25, it is discharged through the valve 38 into the receiver 39 and,after the valve 38 is closed, is discharged through the valve'40. Whenthe water supply is properly adjusted, the temperature of thegas andcarbide is held at about 100 C. or a little higher by the coolingresulting from evaporation of a part of the Water. This is a safetemperature of operation and the amount of moisture carried out by thegas is much less than in ordinary wet generating processes. Thehydratlon is complete and carbide leaves the generator mixed with thehydrate. The-arrangement of valves at the charging and discharging endsof the apparatus-excludes air during the charging and discharging. Theinterlocking of the carbide feed with the rotation of the drum ensures aproper rate of feed so that only the water supply need be adjusted andonce this adjustment is obtained the generator requires no attentionbeyond char ing fresh carbide into the receptacle 11 ant? removinghydrate from the receiver 25.

' The amount of water present at any instant is much less than isnecessary for complete hydration of the carbide present at the sameinstant, with the result that the small amount of water contacting thecarbide at any instant is immediately an almost entirely taken up in thehydration reaction. Only a small proportion of this water is absorbed bythe hydrate, so that the hydrate which forms at the surface of thecarbide lumps is'for all practical purposes a dry powder which separateseasily from the carbide.

Having thus described my invention, what I claim is 1. In an acetylenegenerator, a rotatable v cylindrical drum,

, tive by means to supply-water to the carbide in the the drum coaxiallyscreen,

, ends of the drum located in axial alignment screen. p

2. In an acetylene generator, a rotatable cylindrical drum, hollowtrunnions at the ends of the drum located in axial alignment therewithrotatably supporting the drum, a cylindrical screen 'of smaller diameterthan the drum fixed within the drum coaxially thereof, said screen beingspaced atone end from the adjacent end of the drum, means to rotate thedrum andfscreemmeans to feed. carbide through one of said trunni'onsinto the screen, means to remove hydrate from the drum, at the endthereof spaced from the screen, through the second trunnion, a gas tightreceiver for hydrate and gas into which the second trunnion enters, andmeans to sup ply water to the carbide in the drum.

1 3. In an acetylene generator, a rotatable cylindrical drum, acylindrical screen of smaller diameter thanthe drum fixed withinthereof, and extending from one end ofthe drum part way to the otherend, means to rotate the drum nd neans to move material pas ing thescreen longitudinally of the theend of the through drum into the spacebetween drum and the end of the screen, means to tumble material in saidspace, means to feed carbide into the screen, means to remove hydratefrom the drum and means to supply water to the carbide in thescreen.

4. In an acetylene generator, ra rotatable cylindrical drum, hollowtrunnions at the therewith rotatably supporting the drum, a

. cylindrical screen of smaller diameter than the drum fixed withinthedrum coaxially thereof, extending from one end of the drum 3 part wayto the other end, means to rotate the drum and screen. helical ribsfixed to the inner surface of the drum outside the screen 'to movematerialpassing through the screen longitudinally of the drum' into thespace between the end of the drum and the'end of the screen, of the drumin said space axially parallel with thefdrum, a discharge cone arrangedin said space coaxially withthe drum and havribs secured to the innersurface into the first, conduit, a valve at the exit end of the secondconduit, a closed carbide container arranged to feed carbide into thesecond conduit, and means for operating both of said carbide movingmeans to move carbide at the same rate in the two conduits.

6. A device according to claim 1, in which the water supplying meansisadapted to direct water in a' fine spray on only of the carbide, on theupwardl of the screen, which is at an limit of its angle of repose. 7 1

7. In an acetylene generator, means to spray lump carbide with water, ascreening device to separate'hydrate from the surface moving side thatportion adjacent the of the sprayed carbide lumps and to remove thedamphydrateand small particles of carbide from contact with the carbidelumps, means to tumble the damp hydrate andsmall carbide particlesseparately from the carbide lumps until the small particles arecompletely hydrated by the water content of the hydrate and the hydratethereby dried, means to remove dry hydrate and acetylene gas togetherfrom said tumblin means and means connectedfto the tumb ing means. inwhich the gas is separated from "the dry hydrate.

8. In an acetylene generator, a rotatable cylindrical drdm, hollowtrunnions at the ends of the drum located in axial alignment therewithand rotatably supportingithe drum, a cylindrical, screen of smallerdiameter than the one end material which has passed through the screenand to advance the material into the space ,between the end of thescreen and .the adj acentdrum fixed in the drum, coaxiallythereof, saidscreen being spaced at from theadjacent end ofthe drum, means torotatethe drum and screen, means to feed carbide throughone of saidtrunnions' .into the screen, means to tumble in the drum vance' materialthrough the trunnion away from the drum.

In witness whereof, I have hereunto set m hand. i ROBERT S.'.IANE.

ing its apex projecting into the. adjacent trunnion, helical ribs withinsaid-trunnion to move material through the trunnlon away from the drum,a gas-tight receiver for hy- 'drate and 'gas into which the secondtrunnion enters, and means carbide in the drum.-

5. A device according to claim 2, inwhich the carbide feeding meanscomprises a con-v to supply water to the

